I want to overclock my processor its a P4 2.66 Ghz and as I've stated in the title its cold the temp of my processor was always at 40-50C now its below 36C - 34C the lowest I've seen it. And I've been running the the PC for a good 30mins.

the max operating temp for that CPU is about 64c. you can OC and watch temps....but if you have a stock HS/F on it, its will get to maximum temp in a hurry, so be careful. you probably dont want to rely on a cold snap as your cooling solution...if your wife cant find her snuggy and turns up the heat....your screwed. LOL

Is that your main computer? If it is I would just leave it be, thats some old hardware and if thats what you got as your main rig, last thing you want to do is have it crap out on you. Now if your just trying to set some personal records OC away!

It currently is my main PC yes, but I've OC'd and the max speed I've gotten the processor @ is around 2.87Ghz whenever I go any higher its like the BIOS change it back to its default settings.

that processor is barely worth the overclock... you're probably not going to notice any significant changes other than heat. I mean going from 2.66ghz to 2.87ghz is nothing lol, especially if the temps jump up. you're more likely to fry the thing before you notice any real performance boosts.